The present invention relates to an improved grip for racquets and other devices employing handles that are subject to shock when such devices are impacted, as for example, tennis ball racquets, racquetball racquets, golf clubs, baseball bats and hammers.
It is well known that shock generated by impact between a device such as a tennis racquet and a tennis ball can affect muscle tissue and arm joints such as elbow joints. Such shock often results in "tennis elbow" which is a painful affliction commonly experienced by active tennis players. Medical theories attribute "tennis elbow" to continuous exposure of the playing arm of a tennis player to shock and vibration generated by striking a tennis ball with a tennis racquet. The energy generated is usually of high frequency and short duration with rapid decay, and which is often known as "impact shock." Tight grasping of a grip to keep it from slipping contributes to "tennis elbow." Various types of grips have been proposed for inhibiting "tennis elbow," however, such grips have not solved such problem. The grip of the present invention successfully reduces or even eliminates "tennis elbow" type shock to the muscle tissue and arm joints of the users of tennis racquets, racquetball racquets, golf clubs, baseball bats, and other impact imparting devices such as hammers.
Conventional prior art grips of this type have conventionally utilized a layer of polyurethane backed with a layer of felt. In general, the felt layer has a thickness of about 1.40 mm. The polyurethane layer is generally thinner than 0.25 mm, and has been considered only as providing tackiness, i.e., resistance to the slip caused by a sweaty hand. The polyurethane has not been considered to be useful for inhibiting shock. The felt was relied upon to cushion the user's arm and hand against the shock created when the ball hits the racquet.
Applicant has previously developed resilient grips which successfully reduce or even to eliminate "tennis elbow" type shock to the muscle and arm joints of the users of tennis racquets, racquet ball racquets, golf clubs, baseball bats and other impact imparting devices such as hammers. See, for example, U.S. Pat. No. 5,374,059 granted to applicant Dec. 20, 1994. Such earlier grips utilize a polyurethane layer bonded to a felt layer to define a strip which is spirally wrapped around the handle of a racquet or the like to conform to the external configuration of such handle. In such earlier grips of applicant's design the thickness of the polyurethane layer relative to the thickness of the felt layer as compared to prior art resilient grips, i.e. the ratio of the thickness of the polyurethane layer to the thickness of the felt layer was a minimum of approximately 0.18, with the thickness of the polyurethane layer having been about equal to or thicker than the thickness of the textile layer in a typical grip of my design. In such grips the handle-abutting side of the strip utilized skiving, with the felt layer tapering from a transverse central region upwardly and outwardly towards the transverse side edges of the strip. The side edges of the strip were overlapped as the strip was wrapped around the handle so that the strip did not have a smooth configuration along its length. Additionally, the skiving tended to weaken the grip. Moreover, the side edges of the strip tended to unravel in use. It was also determined that where the strip was not properly applied to the handle, the grip would tend to loosen relative to the handle.
It is also known that golfers commonly sustain injuries resulting from shock transferred from a golf club to the golfer's back, wrists, elbows, shoulders and knees during a golf swing.